Add get_all_called_routine function to CallTreeUtils

[hiker]

ATM the call tree utilities return all symbols used, but there is no (easy) way to get name and location of all routines called. Add this functionality, which will likely require a refactoring of the existing functionality to avoid code duplication - I expected that the get all symbols functionality will first call get all routines, then query all the subroutines (while atm this is done all at once).

[arporter]

I must be missing something here Joerg. Why isn't it as a simple as routines = [call.routine for call in psyir.walk(Call)]? Is it because of function 'calls' that we don't spot?

[sergisiso]

They should now also be returned by node.reference_access() and filter for AccessType.CALLED

[hiker]

Ah, I should have mentioned recursively - this will follow the whole (static) call tree (as far as possible that is).

[hiker]

I'll find a better name. As an example, here what my (currently still hacky) branch does (call_tree.py just prints the output of this function):

  psyclone -l output --psykal-dsl lfric -s ./call_tree.py \
                     -d... .../casim_alg_mod.x90
        [('casim_code', 'casim_kernel_mod'),
        ('mphys_air_density', 'mphys_air_density_mod'),
        ('dr_hook', 'yomhook'),
        ('allocate_diagnostic_space', 'generic_diagnostic_variables'),
        ('shipway_microphysics', 'micro_main'),
        ('zero_procs', 'process_routines'),
        ('set_passive_fields', 'passive_fields'),
        ('throw_mphys_error', 'mphys_die'),
        ('ereport', 'ereport_mod'),
        ('log_event', 'log_mod'),
        ('traceback', 'traceback_mod'),
        ('abort_model', 'log_mod'),
        ('microphysics_common', 'micro_main'),
        ('tidy_qin', 'mphys_tidy'),
        ('recompute_qin_constants', 'mphys_tidy'),
        ('casim_reflec', 'casim_reflec_mod'),
        ('query_distributions', 'distributions'),
        ('get_slope_generic_kf', 'lookup'),
        ('casim_moments', 'casim_moments_mod'),
        ('get_lam_n0_3m', 'lookup'),
        ('get_lam_n0_2m', 'lookup'),
        ('get_lam_n0_1m', 'lookup'),
        ('get_lam_n0_1m_kf', 'lookup'),
        ('get_slope_generic', 'lookup'),
        ('deallocate_diagnostic_space',
        ('generic_diagnostic_variables')]

NIWA started to do this kind of analysis manually to identify the scope of work required to get (all) of a function on GPU.